Originally Posted by SSGN_Doc
There are piston kits that the home builder can use.
I think the AR works pretty darn well with the DI gas system though. Some if the puston kits bring their own set of problems to the AR.
kits add about the weight of a roll of pennies to the AR, depending on which brand, and if you don't have enough mechanical skill to install one, can create more problems than they help. I think I have installed more piston kits than anyone on this forum. I have installed 3 brands; (a) ARES (b) Osprey (c) TNW. All presented their own unique challenges. Some common factors are:
They don't eliminate
carbon. They just push it to an easier to get to place.
I don't recommend you use them as a shortcut to troubleshooting or solving a malfunction. In most occasions, spending time with your AR on a table or workbench is better than throwing money at an easily fixed solution. When I install a piston system, I do it as a part of a build, and as a result every aspect of the build I am thinking of how it will work with the piston.
I usually get slickside uppers, as the need for a forward assist is eliminated by removal of the gas rings.
Sometimes when shooters start talking of putting a piston system in, they have an AR that someone or factory did a half assed build on, and they are frustrated that their knowledge is not sufficient to resolve an issue, and people who are supposedly knowledgeable give them bad advice. Unlike what my Drill Sergeants were preaching in basic, you cannot always clean your gun into a repair. If the barrel nut wasn't perfectly straight when the barrel is installed, the gas tube will be at an angle, and you lose gas pressure to cycle the bolt carrier group. If you can hold the bolt face and shake the BCG a little and the carrier drops down a little, your gas rings are worn and need to be replaced. If you buy your gas rings at Brownell's in bulk, you can usually get them for an average of $1 to $1.25 a set. Much cheaper than a piston. You can learn to install a barrel and only cost you the cost of the AR wrench, the barrel, and the gas tube roll pin.
I am one of the biggest piston proponents, but I think before you invest in a piston system, you should get to know your AR and how and why things work on it.
I have a DI 20" AR, and it functions just fine. If your AR is not cycling properly, I suggest you trouble shoot the problem. You might just find you can make it into a highly reliable firearm for not much money with a little effort.